In the mirror universe, Duras was a prominent Klingon warrior and politician who lived during the 24th century. He was the son of Ja'rod, the brother of Lursa and B'Etor and a descendant of his namesake Councillor Duras. Due to his family's decades long enmity with the House of Mogh, Duras had to call in a favor which was owed to him in order to retain his command after Mogh's son, Worf, became the Regent of the Klingon Empire in the early 2370s. (TNG - Mirror Universe novel: Rise Like Lions)